Merge to Fedora kernel-2.6.18-1.2224_FC5 patched with stable patch-2.6.18.1-vs2.0...
[linux-2.6.git] / net / tipc / name_table.c
index d129422..049242e 100644 (file)
@@ -71,7 +71,7 @@ struct sub_seq {
  * @sseq: pointer to dynamically-sized array of sub-sequences of this 'type';
  *        sub-sequences are sorted in ascending order
  * @alloc: number of sub-sequences currently in array
- * @first_free: upper bound of highest sub-sequence + 1
+ * @first_free: array index of first unused sub-sequence entry
  * @ns_list: links to adjacent name sequences in hash chain
  * @subscriptions: list of subscriptions for this 'type'
  * @lock: spinlock controlling access to name sequence structure
@@ -101,7 +101,7 @@ struct name_table {
 
 static struct name_table table = { NULL } ;
 static atomic_t rsv_publ_ok = ATOMIC_INIT(0);
-rwlock_t tipc_nametbl_lock = RW_LOCK_UNLOCKED;
+DEFINE_RWLOCK(tipc_nametbl_lock);
 
 
 static int hash(int x)
@@ -117,14 +117,12 @@ static struct publication *publ_create(u32 type, u32 lower, u32 upper,
                                       u32 scope, u32 node, u32 port_ref,   
                                       u32 key)
 {
-       struct publication *publ =
-               (struct publication *)kmalloc(sizeof(*publ), GFP_ATOMIC);
+       struct publication *publ = kzalloc(sizeof(*publ), GFP_ATOMIC);
        if (publ == NULL) {
-               warn("Memory squeeze; failed to create publication\n");
+               warn("Publication creation failure, no memory\n");
                return NULL;
        }
 
-       memset(publ, 0, sizeof(*publ));
        publ->type = type;
        publ->lower = lower;
        publ->upper = upper;
@@ -144,11 +142,7 @@ static struct publication *publ_create(u32 type, u32 lower, u32 upper,
 
 static struct sub_seq *tipc_subseq_alloc(u32 cnt)
 {
-       u32 sz = cnt * sizeof(struct sub_seq);
-       struct sub_seq *sseq = (struct sub_seq *)kmalloc(sz, GFP_ATOMIC);
-
-       if (sseq)
-               memset(sseq, 0, sz);
+       struct sub_seq *sseq = kcalloc(cnt, sizeof(struct sub_seq), GFP_ATOMIC);
        return sseq;
 }
 
@@ -160,22 +154,20 @@ static struct sub_seq *tipc_subseq_alloc(u32 cnt)
 
 static struct name_seq *tipc_nameseq_create(u32 type, struct hlist_head *seq_head)
 {
-       struct name_seq *nseq = 
-               (struct name_seq *)kmalloc(sizeof(*nseq), GFP_ATOMIC);
+       struct name_seq *nseq = kzalloc(sizeof(*nseq), GFP_ATOMIC);
        struct sub_seq *sseq = tipc_subseq_alloc(1);
 
        if (!nseq || !sseq) {
-               warn("Memory squeeze; failed to create name sequence\n");
+               warn("Name sequence creation failed, no memory\n");
                kfree(nseq);
                kfree(sseq);
                return NULL;
        }
 
-       memset(nseq, 0, sizeof(*nseq));
-       nseq->lock = SPIN_LOCK_UNLOCKED;
+       spin_lock_init(&nseq->lock);
        nseq->type = type;
        nseq->sseqs = sseq;
-       dbg("tipc_nameseq_create() nseq = %x type %u, ssseqs %x, ff: %u\n",
+       dbg("tipc_nameseq_create(): nseq = %p, type %u, ssseqs %p, ff: %u\n",
            nseq, type, nseq->sseqs, nseq->first_free);
        nseq->alloc = 1;
        INIT_HLIST_NODE(&nseq->ns_list);
@@ -253,16 +245,16 @@ static struct publication *tipc_nameseq_insert_publ(struct name_seq *nseq,
        struct sub_seq *sseq;
        int created_subseq = 0;
 
-       assert(nseq->first_free <= nseq->alloc);
        sseq = nameseq_find_subseq(nseq, lower);
-       dbg("nameseq_ins: for seq %x,<%u,%u>, found sseq %x\n",
+       dbg("nameseq_ins: for seq %p, {%u,%u}, found sseq %p\n",
            nseq, type, lower, sseq);
        if (sseq) {
 
                /* Lower end overlaps existing entry => need an exact match */
 
                if ((sseq->lower != lower) || (sseq->upper != upper)) {
-                       warn("Overlapping publ <%u,%u,%u>\n", type, lower, upper);
+                       warn("Cannot publish {%u,%u,%u}, overlap error\n",
+                            type, lower, upper);
                        return NULL;
                }
        } else {
@@ -277,25 +269,27 @@ static struct publication *tipc_nameseq_insert_publ(struct name_seq *nseq,
 
                if ((inspos < nseq->first_free) &&
                    (upper >= nseq->sseqs[inspos].lower)) {
-                       warn("Overlapping publ <%u,%u,%u>\n", type, lower, upper);
+                       warn("Cannot publish {%u,%u,%u}, overlap error\n",
+                            type, lower, upper);
                        return NULL;
                }
 
                /* Ensure there is space for new sub-sequence */
 
                if (nseq->first_free == nseq->alloc) {
-                       struct sub_seq *sseqs = nseq->sseqs;
-                       nseq->sseqs = tipc_subseq_alloc(nseq->alloc * 2);
-                       if (nseq->sseqs != NULL) {
-                               memcpy(nseq->sseqs, sseqs,
-                                      nseq->alloc * sizeof (struct sub_seq));
-                               kfree(sseqs);
-                               dbg("Allocated %u sseqs\n", nseq->alloc);
-                               nseq->alloc *= 2;
-                       } else {
-                               warn("Memory squeeze; failed to create sub-sequence\n");
+                       struct sub_seq *sseqs = tipc_subseq_alloc(nseq->alloc * 2);
+
+                       if (!sseqs) {
+                               warn("Cannot publish {%u,%u,%u}, no memory\n",
+                                    type, lower, upper);
                                return NULL;
                        }
+                       dbg("Allocated %u more sseqs\n", nseq->alloc);
+                       memcpy(sseqs, nseq->sseqs,
+                              nseq->alloc * sizeof(struct sub_seq));
+                       kfree(nseq->sseqs);
+                       nseq->sseqs = sseqs;
+                       nseq->alloc *= 2;
                }
                dbg("Have %u sseqs for type %u\n", nseq->alloc, type);
 
@@ -311,7 +305,7 @@ static struct publication *tipc_nameseq_insert_publ(struct name_seq *nseq,
                sseq->upper = upper;
                created_subseq = 1;
        }
-       dbg("inserting (%u %u %u) from %x:%u into sseq %x(%u,%u) of seq %x\n",
+       dbg("inserting {%u,%u,%u} from <0x%x:%u> into sseq %p(%u,%u) of seq %p\n",
            type, lower, upper, node, port, sseq,
            sseq->lower, sseq->upper, nseq);
 
@@ -320,7 +314,7 @@ static struct publication *tipc_nameseq_insert_publ(struct name_seq *nseq,
        publ = publ_create(type, lower, upper, scope, node, port, key);
        if (!publ)
                return NULL;
-       dbg("inserting publ %x, node=%x publ->node=%x, subscr->node=%x\n",
+       dbg("inserting publ %p, node=0x%x publ->node=0x%x, subscr->node=%p\n",
            publ, node, publ->node, publ->subscr.node);
 
        if (!sseq->zone_list)
@@ -367,45 +361,47 @@ static struct publication *tipc_nameseq_insert_publ(struct name_seq *nseq,
 
 /**
  * tipc_nameseq_remove_publ -
+ * 
+ * NOTE: There may be cases where TIPC is asked to remove a publication
+ * that is not in the name table.  For example, if another node issues a
+ * publication for a name sequence that overlaps an existing name sequence
+ * the publication will not be recorded, which means the publication won't
+ * be found when the name sequence is later withdrawn by that node.
+ * A failed withdraw request simply returns a failure indication and lets the
+ * caller issue any error or warning messages associated with such a problem.
  */
 
 static struct publication *tipc_nameseq_remove_publ(struct name_seq *nseq, u32 inst,
                                                    u32 node, u32 ref, u32 key)
 {
        struct publication *publ;
+       struct publication *curr;
        struct publication *prev;
        struct sub_seq *sseq = nameseq_find_subseq(nseq, inst);
        struct sub_seq *free;
        struct subscription *s, *st;
        int removed_subseq = 0;
 
-       assert(nseq);
-
-       if (!sseq) {
-               int i;
-
-               warn("Withdraw unknown <%u,%u>?\n", nseq->type, inst);
-               assert(nseq->sseqs);
-               dbg("Dumping subseqs %x for %x, alloc = %u,ff=%u\n",
-                   nseq->sseqs, nseq, nseq->alloc, 
-                   nseq->first_free);
-               for (i = 0; i < nseq->first_free; i++) {
-                       dbg("Subseq %u(%x): lower = %u,upper = %u\n",
-                           i, &nseq->sseqs[i], nseq->sseqs[i].lower,
-                           nseq->sseqs[i].upper);
-               }
+       if (!sseq)
                return NULL;
-       }
-       dbg("nameseq_remove: seq: %x, sseq %x, <%u,%u> key %u\n",
+
+       dbg("tipc_nameseq_remove_publ: seq: %p, sseq %p, {%u,%u}, key %u\n",
            nseq, sseq, nseq->type, inst, key);
 
+       /* Remove publication from zone scope list */
+
        prev = sseq->zone_list;
        publ = sseq->zone_list->zone_list_next;
        while ((publ->key != key) || (publ->ref != ref) || 
               (publ->node && (publ->node != node))) {
                prev = publ;
                publ = publ->zone_list_next;
-               assert(prev != sseq->zone_list);
+               if (prev == sseq->zone_list) {
+                       
+                       /* Prevent endless loop if publication not found */
+
+                       return NULL;
+               }
        }
        if (publ != sseq->zone_list)
                prev->zone_list_next = publ->zone_list_next;
@@ -416,14 +412,24 @@ static struct publication *tipc_nameseq_remove_publ(struct name_seq *nseq, u32 i
                sseq->zone_list = NULL;
        }
 
+       /* Remove publication from cluster scope list, if present */
+
        if (in_own_cluster(node)) {
                prev = sseq->cluster_list;
-               publ = sseq->cluster_list->cluster_list_next;
-               while ((publ->key != key) || (publ->ref != ref) || 
-                      (publ->node && (publ->node != node))) {
-                       prev = publ;
-                       publ = publ->cluster_list_next;
-                       assert(prev != sseq->cluster_list);
+               curr = sseq->cluster_list->cluster_list_next;
+               while (curr != publ) {
+                       prev = curr;
+                       curr = curr->cluster_list_next;
+                       if (prev == sseq->cluster_list) {
+
+                               /* Prevent endless loop for malformed list */
+
+                               err("Unable to de-list cluster publication\n"
+                                   "{%u%u}, node=0x%x, ref=%u, key=%u)\n",
+                                   publ->type, publ->lower, publ->node, 
+                                   publ->ref, publ->key);
+                               goto end_cluster;
+                       }
                }
                if (publ != sseq->cluster_list)
                        prev->cluster_list_next = publ->cluster_list_next;
@@ -434,15 +440,26 @@ static struct publication *tipc_nameseq_remove_publ(struct name_seq *nseq, u32 i
                        sseq->cluster_list = NULL;
                }
        }
+end_cluster:
+
+       /* Remove publication from node scope list, if present */
 
        if (node == tipc_own_addr) {
                prev = sseq->node_list;
-               publ = sseq->node_list->node_list_next;
-               while ((publ->key != key) || (publ->ref != ref) || 
-                      (publ->node && (publ->node != node))) {
-                       prev = publ;
-                       publ = publ->node_list_next;
-                       assert(prev != sseq->node_list);
+               curr = sseq->node_list->node_list_next;
+               while (curr != publ) {
+                       prev = curr;
+                       curr = curr->node_list_next;
+                       if (prev == sseq->node_list) {
+
+                               /* Prevent endless loop for malformed list */
+
+                               err("Unable to de-list node publication\n"
+                                   "{%u%u}, node=0x%x, ref=%u, key=%u)\n",
+                                   publ->type, publ->lower, publ->node, 
+                                   publ->ref, publ->key);
+                               goto end_node;
+                       }
                }
                if (publ != sseq->node_list)
                        prev->node_list_next = publ->node_list_next;
@@ -453,22 +470,18 @@ static struct publication *tipc_nameseq_remove_publ(struct name_seq *nseq, u32 i
                        sseq->node_list = NULL;
                }
        }
-       assert(!publ->node || (publ->node == node));
-       assert(publ->ref == ref);
-       assert(publ->key == key);
+end_node:
 
-       /* 
-        * Contract subseq list if no more publications:
-        */
-       if (!sseq->node_list && !sseq->cluster_list && !sseq->zone_list) {
+       /* Contract subseq list if no more publications for that subseq */
+
+       if (!sseq->zone_list) {
                free = &nseq->sseqs[nseq->first_free--];
                memmove(sseq, sseq + 1, (free - (sseq + 1)) * sizeof (*sseq));
                removed_subseq = 1;
        }
 
-       /* 
-        * Any subscriptions waiting ? 
-        */
+       /* Notify any waiting subscriptions */
+
        list_for_each_entry_safe(s, st, &nseq->subscriptions, nameseq_list) {
                tipc_subscr_report_overlap(s,
                                           publ->lower,
@@ -478,6 +491,7 @@ static struct publication *tipc_nameseq_remove_publ(struct name_seq *nseq, u32 i
                                           publ->node,
                                           removed_subseq);
        }
+
        return publ;
 }
 
@@ -530,7 +544,7 @@ static struct name_seq *nametbl_find_seq(u32 type)
        seq_head = &table.types[hash(type)];
        hlist_for_each_entry(ns, seq_node, seq_head, ns_list) {
                if (ns->type == type) {
-                       dbg("found %x\n", ns);
+                       dbg("found %p\n", ns);
                        return ns;
                }
        }
@@ -543,22 +557,21 @@ struct publication *tipc_nametbl_insert_publ(u32 type, u32 lower, u32 upper,
 {
        struct name_seq *seq = nametbl_find_seq(type);
 
-       dbg("ins_publ: <%u,%x,%x> found %x\n", type, lower, upper, seq);
+       dbg("tipc_nametbl_insert_publ: {%u,%u,%u} found %p\n", type, lower, upper, seq);
        if (lower > upper) {
-               warn("Failed to publish illegal <%u,%u,%u>\n",
+               warn("Failed to publish illegal {%u,%u,%u}\n",
                     type, lower, upper);
                return NULL;
        }
 
-       dbg("Publishing <%u,%u,%u> from %x\n", type, lower, upper, node);
+       dbg("Publishing {%u,%u,%u} from 0x%x\n", type, lower, upper, node);
        if (!seq) {
                seq = tipc_nameseq_create(type, &table.types[hash(type)]);
-               dbg("tipc_nametbl_insert_publ: created %x\n", seq);
+               dbg("tipc_nametbl_insert_publ: created %p\n", seq);
        }
        if (!seq)
                return NULL;
 
-       assert(seq->type == type);
        return tipc_nameseq_insert_publ(seq, type, lower, upper,
                                        scope, node, port, key);
 }
@@ -572,7 +585,7 @@ struct publication *tipc_nametbl_remove_publ(u32 type, u32 lower,
        if (!seq)
                return NULL;
 
-       dbg("Withdrawing <%u,%u> from %x\n", type, lower, node);
+       dbg("Withdrawing {%u,%u} from 0x%x\n", type, lower, node);
        publ = tipc_nameseq_remove_publ(seq, lower, node, ref, key);
 
        if (!seq->first_free && list_empty(&seq->subscriptions)) {
@@ -738,12 +751,12 @@ struct publication *tipc_nametbl_publish(u32 type, u32 lower, u32 upper,
        struct publication *publ;
 
        if (table.local_publ_count >= tipc_max_publications) {
-               warn("Failed publish: max %u local publication\n", 
+               warn("Publication failed, local publication limit reached (%u)\n", 
                     tipc_max_publications);
                return NULL;
        }
        if ((type < TIPC_RESERVED_TYPES) && !atomic_read(&rsv_publ_ok)) {
-               warn("Failed to publish reserved name <%u,%u,%u>\n",
+               warn("Publication failed, reserved name {%u,%u,%u}\n",
                     type, lower, upper);
                return NULL;
        }
@@ -767,10 +780,10 @@ int tipc_nametbl_withdraw(u32 type, u32 lower, u32 ref, u32 key)
 {
        struct publication *publ;
 
-       dbg("tipc_nametbl_withdraw:<%d,%d,%d>\n", type, lower, key);
+       dbg("tipc_nametbl_withdraw: {%u,%u}, key=%u\n", type, lower, key);
        write_lock_bh(&tipc_nametbl_lock);
        publ = tipc_nametbl_remove_publ(type, lower, tipc_own_addr, ref, key);
-       if (publ) {
+       if (likely(publ)) {
                table.local_publ_count--;
                if (publ->scope != TIPC_NODE_SCOPE)
                        tipc_named_withdraw(publ);
@@ -780,6 +793,9 @@ int tipc_nametbl_withdraw(u32 type, u32 lower, u32 ref, u32 key)
                return 1;
        }
        write_unlock_bh(&tipc_nametbl_lock);
+       err("Unable to remove local publication\n"
+           "(type=%u, lower=%u, ref=%u, key=%u)\n",
+           type, lower, ref, key);
        return 0;
 }
 
@@ -787,8 +803,7 @@ int tipc_nametbl_withdraw(u32 type, u32 lower, u32 ref, u32 key)
  * tipc_nametbl_subscribe - add a subscription object to the name table
  */
 
-void
-tipc_nametbl_subscribe(struct subscription *s)
+void tipc_nametbl_subscribe(struct subscription *s)
 {
        u32 type = s->seq.type;
        struct name_seq *seq;
@@ -800,11 +815,13 @@ tipc_nametbl_subscribe(struct subscription *s)
        }
         if (seq){
                 spin_lock_bh(&seq->lock);
-                dbg("tipc_nametbl_subscribe:found %x for <%u,%u,%u>\n",
+                dbg("tipc_nametbl_subscribe:found %p for {%u,%u,%u}\n",
                     seq, type, s->seq.lower, s->seq.upper);
-                assert(seq->type == type);
                 tipc_nameseq_subscribe(seq, s);
                 spin_unlock_bh(&seq->lock);
+        } else {
+               warn("Failed to create subscription for {%u,%u,%u}\n",
+                    s->seq.type, s->seq.lower, s->seq.upper);
         }
         write_unlock_bh(&tipc_nametbl_lock);
 }
@@ -813,8 +830,7 @@ tipc_nametbl_subscribe(struct subscription *s)
  * tipc_nametbl_unsubscribe - remove a subscription object from name table
  */
 
-void
-tipc_nametbl_unsubscribe(struct subscription *s)
+void tipc_nametbl_unsubscribe(struct subscription *s)
 {
        struct name_seq *seq;
 
@@ -1036,7 +1052,7 @@ int tipc_nametbl_init(void)
 {
        int array_size = sizeof(struct hlist_head) * tipc_nametbl_size;
 
-       table.types = (struct hlist_head *)kmalloc(array_size, GFP_ATOMIC);
+       table.types = kmalloc(array_size, GFP_ATOMIC);
        if (!table.types)
                return -ENOMEM;
 
@@ -1049,35 +1065,20 @@ int tipc_nametbl_init(void)
 
 void tipc_nametbl_stop(void)
 {
-       struct hlist_head *seq_head;
-       struct hlist_node *seq_node;
-       struct hlist_node *tmp;
-       struct name_seq *seq;
        u32 i;
 
        if (!table.types)
                return;
 
+       /* Verify name table is empty, then release it */
+
        write_lock_bh(&tipc_nametbl_lock);
        for (i = 0; i < tipc_nametbl_size; i++) {
-               seq_head = &table.types[i];
-               hlist_for_each_entry_safe(seq, seq_node, tmp, seq_head, ns_list) {
-                       struct sub_seq *sseq = seq->sseqs;
-
-                       for (; sseq != &seq->sseqs[seq->first_free]; sseq++) {
-                               struct publication *publ = sseq->zone_list;
-                               assert(publ);
-                               do {
-                                       struct publication *next =
-                                               publ->zone_list_next;
-                                       kfree(publ);
-                                       publ = next;
-                               }
-                               while (publ != sseq->zone_list);
-                       }
-               }
+               if (!hlist_empty(&table.types[i]))
+                       err("tipc_nametbl_stop(): hash chain %u is non-null\n", i);
        }
        kfree(table.types);
        table.types = NULL;
        write_unlock_bh(&tipc_nametbl_lock);
 }
+